If you're running stable or testing, how do you tell apt how to get packages from unstable ? Running

apt-get install kscreensaver/unstable

results in a

E: Release 'unstable' for 'kscreensaver' was not found

error message. If I add a deb line to sources.list file to include the unstable tree as well, apt-get install wants to upgrade *lots* of packages.

TIA -

D.